1. You have the following stream of a firm's cash flows, assume that the firm's opportunity cost is 20%. Year Amount $5,000 1 2 $ 20,000 3 $ 15,000 If these cash flows received at the end of each period. Calculate the present value of the firm's cash flows? Choose... . If these cash flows received at the beginning of each period. Calculate the future value of the firm's cash flows? > Choose... If these cash flows received at the end of each period. Calculate the future value of the firm's cash flows? Choose... If these cash flows received at the beginning of each period. Calculate the present value of the firm's cash flows? Choose